Alfred P. Sloan Foundation

STEM Research

Sloan Digital Sky Survey

The Sloan Digital Sky Survey (SDSS) is one of the largest, most detailed, and most often cited astronomical surveys that has ever existed, with the goal of expanding our understanding of the large-scale evolution and structure of the universe, the formation of stars and galaxies, the history of the Milky Way, and the science behind dark energy. By comprehensively mapping and cataloguing over a third of the night sky, SDSS represents one of the major quests of contemporary physics and has spurred advancement on answering a range of fundamental questions about the origins of the universe.

In cooperation with the Astrophysical Research Consortium, the Foundation has helped build and operate a pioneering, specially designed telescope and experiments to observe and archive information on millions of stars, galaxies, quasars, and other cosmological phenomena. SDSS is distinctive within the astronomical community for its participatory, bottom-up scientific research planning process. SDSS currently involves over 50 contributing institutional members that participate in the collaboration. For the first time in the collaboration’s history, the current fourth phase of SDSS (SDSS-IV) will continue the survey’s rich tradition of data collection by partnering with a sister telescope located in the Southern hemisphere that will allow for observation of regions of the sky not visible from the Northern hemisphere, helping to fully realize the truly global nature of the collaboration.

All SDSS data is eventually released to the public under open principles. Participating scientists have written over 1,000 papers using SDSS data, and a total of 5,800 papers with 245,000 citations have been produced when the use of public data releases is considered. As the only astronomy project supported by the Foundation, SDSS is currently the Foundation’s longest running scientific research program. SDSS-IV is expected to operate until the end of the decade.